Acoustic sensor for detection and identification of microbial cells directly in the liquid phase

A sensor for the analysis of microbial cells based on a PZT ceramic resonator with a lateral electric field is presented. In this resonator, the shear component of the mechanical displacement, which does not lead to radiation loss at the contact with liquid, is prevailing. The frequency dependences of the real and imaginary parts of the electrical impedance of the resonator in the frequency range 50–300 kHz showed the presence of three resonances at frequencies of 68.7, 97.8 and 264 kHz. The possibility of the detection and identification of microbial cells by recording their specific interaction with antibodies, bacteriophages and mini-antibodies directly in suspension using this sensor has been shown.